Chapter 17 Preserving Earth’s Biological Diversity

1. Chapter 17Preserving Earth’s Biological Diversity

2. Overview of Chapter 17 • Biological Diversity • Why we need organisms • Endangered and Extinct Species • Where is Declining Diversity the Greatest Problem • Human Causes of Species Endangerment • Conservation Biology • Protecting and Restoring Habitats • Conservation Policies and Laws • Wildlife Management

3. Biological Diversity • Biological Diversity • Number, variety and variability of Earth’s organisms • Consists of three components: • Genetic diversity (right) • Species richness • Ecosystem diversity

4. Why We Need Organisms • Example contributions to human life: • Food • Clothing • Shelter • Pollination of crops • Antibiotics and medicines • Biological processes (nitrogen fixation) • Biological Diversity represents an untapped resource for future uses

5. Ecosystem Services and Species Richness • All organisms are interrelated • Linked to each other and the physical environment • Ecosystem services • Important environmental benefits that ecosystems provide to people • Clean air • Clean water • Fertile soil • Removal of a species from a community can decrease ecosystem services

6. Scientific Importance of Genetic Diversity • Genetic Engineering • Incorporation of genes from one organism into a different species • Provided: • new vaccines • More productive farm animals • Agricultural plants with desirable characteristics • Depends on genetic diversity from which it obtains genes (cannot create genes) • Important to protect this diversity

7. Medical Importance of Organisms • Genetic Resources are important to pharmaceutical industry • Ex: Rosy Periwinkle (right) • Produces chemicals effective against certain types of cancer • Ex: aquatic sponge • Produces derivative for the drug AZT used to treat AIDS

8. Agricultural and Industrial Importance of Organisms • Agricultural Importance • Numerous species that are nutritionally superior to the food we eat • Industrial Importance • Depends on products from organisms • Oils and lubricants • Perfumes and fragrances • Dyes • Paper and lumber • poisons

9. Extinct Species • Extinction • Elimination of a species from Earth

10. Extinct Species

11. Endangered and Threatened Species • Earth’s biological diversity is disappearing at an unprecedented rate • Endangered Species • Species that faces threats that may cause it to become extinct within a short period • Threatened Species • Species whose population has declined to the point that it may be at risk of extinction

12. Characteristic of Endangered Species • Extremely small (localized) range • Requiring a large territory • Living on an island • Having a low reproductive success • Small population size • Low reproductive rates • Requiring specialized breeding areas • Having specialized feeding habitats

13. California Condor • Scavenger bird • Requires large, undisturbed territory • 1983- only 22 birds • 1987-1992- no longer found in nature • 1992- reintroduced to nature from zoos • Currently- 200 condors in nature

14. Where is Declining Biological Diversity the Greatest Problem? • Concern throughout the US • US- Most serious in: • Hawaii (63% of species at risk) • California (29% of species at risk) • Globally- Most serious in tropical rain forests • South and Central America • Central Africa • SE Asia

15. Earth’s Biodiversity Hotspots

16. Human Causes of Species Endangerment

17. Human Cause- Land Use Change • Destruction, fragmentation or degradation of habitats • Little habitat remains for many endangered species

18. Human Cause- Invasive Species

19. Human Cause- Overexploitation

20. Human Cause- Pollution • Examples: Acid rain, ozone depletion, climate warming, excessive fertilizer, industrial wastes

21. Case-In-Point Disappearing Frogs • Amphibians are indicator species • In US 38% of amphibian species are declining • No single cause has been identified • Deformities have also been identified (right)

22. Conservation Biology • Scientific study of how humans impact organisms and the development of ways to protect biodiversity • Involves: • Protecting habitats • Restoring damaged or destroyed habitats • Zoos, aquaria, botanical gardens • Seed banks

23. Protecting Habitats

24. Restoring Damaged Habitats • Restoration ecology • Study of the historical condition of a human-damaged ecosystem • Goal is to return it to its former state • Benefits • Creates biological habitats • Regeneration of soil damaged by agriculture or mining • Disadvantages • Expensive • Take a long time to restore an area

25. Restoring Damaged Habitats Left: (1935) Early stages of prairie restoration Right: (current day) restored prairie

26. Zoos, Aquaria and Botanical Garden • Save organisms from extinction • Artificial insemination • Embryo transfer • Surrogate mothers (right) • Goal is to reintroduce organisms back to their natural habitat

27. Seed Banks • Stored seeds are safe from habitat destruction, climate warming, etc. • Can use seed banks to reintroduce extinct plant species • Some seeds cannot be stored

28. Conservation Policies and Laws • Endangered Species Act (ESA) • 1973 • Authorized protection of endangered and threatened species

29. Conservation Policies and Laws • Endangered Species Act • Species are designated as endangered or threatened based on biological grounds • Controversial Legislation • Does not provide compensation for private property owners who suffer financial loss • Was not reauthorized in 1992 as scheduled • Private property rights vs. conservation • Financial cost of law

30. Conservation Policies and Laws • Habitat Conservation Plans • 1982 Amendment to ESA • Way to resolve conflicts between development interests and protection of endangered species • Landowner may take a rare species • IF taking does not threatened the survival of recovery of the species on that property • Landowner must set aside land for species

31. Conservation Policies and Laws • International Conservation: • World Conservation Strategy (1980) • Convention on Biological Diversity • Convention on International Trade and Endangered Species of Wild Flora and Fauna (CITES) (1975)

32. Wildlife Management • Application of conservation principles to manage wild species and their habitats for human benefit or for the welfare of other species • Different priorities than conservation biology • Wildlife managers concerned with common species • Conservation biologist concerned with threatened or endangered species

33. Wildlife Management • Migratory Animals • Ex: Artic Snow Geese- increase in population has damaged much of Arctic fragile coastal ecosystem (below)

34. Wildlife Management • Aquatic Organisms • Must be managed to ensure they are not overexploited to the point of extinction • Freshwater fishes • Laws regulate time of year, size of fish and maximum allowable catch • Ocean fishes • Ocean fisheries often viewed as common property • Many whale species have been harvested to point of commercial extinction

35. You Can Make A Difference • Increase public awareness of the importance of biological diversity • Join and actively support conservation organization • Inform state and national politicians of desire to have conservation research funded with tax dollars • Establish parks by writing to national lawmakers • Control pollution